The technical scope of the present invention is that of devices allowing a priming system to be attached to the body of a grenade, and notably a shaped charge grenade intended to be carried on-board and scattered by a projectile (shell or rocket) during its trajectory.
Priming systems for such grenades are generally attached to the grenade by riveting or screwing.
U.S. Pat. No. 3,913,483 thus describes a priming system attached by riveting.
Such attachment means do not allow the priming system to be easily replaced by a new system, for example a more effective system, incorporating for example a self-destruct device.
The rivets must be cut and can therefore no longer be used to attach the new priming system.
The grenade body can therefore not be reused and the grenade must be entirely replaced.
The aim of the present invention is to supply a device to attach a priming system onto the body of a grenade that allows, reliably and economically, the subsequent replacement of the priming system.
A further subject of the invention is a process allowing a priming system and a grenade body to be easily joined together.
The process according to the invention allows such joining within the scope of the updating of a grenade store.
In fact, it allow an old priming system to be replaced by a new priming system, even if the latter is different in shape, materials and dimensions to the former priming system.
Thus, the subject of the invention is a device to attach a priming system onto the body of a grenade, such device characterised in that it is formed by a support made integral by fastening means on the grenade body, such support incorporating a thin cylindrical wall whose upper edge is crimped onto the priming system.
According to a first embodiment, the support can be constituted by a cup having a bottom wall integral with the cylindrical wall and placed pressing on an upper face of the grenade.
The cup will have, for example, at least two holes allowing the shanks integral with the grenade body to pass through.
The cup can be made integral with the shanks by welding.
According to a second embodiment, the support can be formed by a tube that is fastened by welding at an external wall of the body.
The external wall onto which the tube is fastened can incorporate a shoulder constituting an abutment for the tube.
The external wall onto which the tube is fastened can be rounded, the end of the tube in this case having a flared part and a bevel.
A further subject of the invention is a process to attach a priming system to a grenade body, such process characterised by the following steps:
a portion of a metallic tube is cut,
part of the external surface of a grenade body is capped by this tube portion,
the tube portion is welded to the grenade body,
the priming system is placed inside the tube,
the tube is crimped onto the priming system.
A further subject of the invention is another process to attach a priming system to a grenade body, such process characterised by the following steps:
a portion of a metallic tube is cut,
a collar forming a crimping abutment is made at one end of the tube, before it is placed around a priming system or else after having placed it around a priming system,
part of the external surface of a grenade body is capped by the tube carrying the priming system,
the tube portion is welded to the grenade body.
Advantageously, when that part of the grenade body onto which the tube is applied is rounded, the tube will be slightly flared before or during its positioning onto the grenade body, this in order to enlarge the relative contact surface between the tube and the grenade body.
Welding can be made by laser.
Laser welding can be made so as to cut one end of the tube so as to arrange a bevelled edge at this end of the tube.